Under Billing Management, click Balance
If you already have a payment method saved agains your account you can pay individual documents by clicking on the ID or Doc. Num of the document you would like to pay, followed by clicking on the “Pay this document” button and follow the on screen prompts.
If you want to make a payment on a new card tick the documents you would like to pay, followed by the “Pay Documents by New Payment” button.
Follow the on-screen prompts to enter your payment details.